Listening, really listening

So what does it take to really listen? I have probably been a poor listener all my life, but have only become aware of it in the last 20 years or so, and really started thinking about the qualities that make a good listener.
A friend did me a favour in my 30s. We were sitting in the kitchen having a rave with another friend. Both were from interstate so I didn't see them very often. Anyway this friend was talking about a topic, and I picked up on something she said within that topic that really interested me. So I asked a question on that aspect, but it wasn't pertinent to the whole topic, it was a sideline. She refused to answer my question, even though I asked it twice. This got me thinking. I felt snubbed but had the sense to explore why she might not have answered. It was not that she was a cruel person. After some consideration, I realised that I was following my own interests not hers, so I had sidelined the conversation into my own agenda.
And this is the key - if you are listening to someone, how hard is it not to start thinking your own thoughts? And then to follow through? I had this really badly in my 30s as I was in emotional and mental anguish, and was very fearful when I interacted with people. So was always thinking 'When they stop talking I will have to say something, but what?' This of course did not make me a good listener, amongst other things, and I was very lonely.
Thankfully things have improved but it has taken a long time and I am still training myself to be a good listener. So what is good listening? I think it is when you are detached enough from yourself and your own thoughts to be able to listen to someone else and what they are really saying. If you are an excellent listener you can hear what is behind the words as well, and maybe enlighten them with some observation they weren't aware of. That is doing them a real favour and enriching the interaction - quality time. Another advantage of this sort of communication is it becomes more spontaneous, even creative, and can lead anywhere, and somewhere that is of interest to you that you hadn't even dreamed of.
It is a goal that I haven't yet achieved, but am improving in daily as I become more mindful. Where have I failed most? In my own backyard. My son has made me aware since his teens or even earlier of what a crap listener I am. I often interrupt him or go off on my own thoughts. This was an anguish of my own childhood (as the youngest) and caused me huge pain in later years. So it is both believable and unbelievable that I am doing the same with my own child. I can only improve....and it is never too late.